We know that during the Little Ice Age that Europeans switched from a mainly cereal diet to potatoes because the cereals couldn't handle the harsh droughts followed by gully washer rains as well as potatoes could. No telling how much real climate change (not the Dim version of climate change) impacted diets from before man started writing history.
The Little Ice Age started to warm up around 1715, well before industrial processes made any significant CO2 contributions. So how much of current warming is natural and how much man made? They simply do not know because both the periodicity and amplitude of the natural changes are not understood.
In contrast, the economic costs of "decarbonisation" (i.e., de-industrialization) are, however, quite well known. So in all likelihood we'll incur enormous costs for zero benefit. What the elite likes is that among those costs are the complete capture of the economy by the ruling elite via hyper-regulation and restriction on freedom of expression and political choice because of the climate "emergency."
And the fact that the enormous emissions of China and India will be ignored seems to indicate with some certainty that theft and political tyranny are the real goals and not suppression of "climate change."